The CFAR Flow Cytometry is heavily used by investigators in all programs of the Center. The core provides education and consultations with CFAR members concerning the potential uses of this powerful method of analysis, and the appropriate design of experiments. Core provides an array of innovative measurements in addition to the usual 3- color surface phenotyping of lymphocytes. Our instrumentation consists of 2 FACSCAN and 2 Profile analytical flow cytometers, each equipped for three-color detection, a Becton Dickinson (BD) FACSCalibur and a B.D. Vantage dual laser sorting instrument with a cloning deposition device. This instrument is located in a negative air pressure room with BL-3 category air filtration and HEPA filtration of all air leaving the instrument. This enable us to sort infected cells. Charge back fees to scientists using the facility provide partial recovery of costs.